Process of tanning hides



W. HARRIS.

PROCESS OF TANNING HIDES. I

Patented Nov. 29,1881.

Inventm VVitness UNITED STATES PATENT OFFICE.

WILLIAM HARRIS, OF FOREST CITY, ASSIGNOR OF ONE-HALF TO THOMAS N. EGERY, OF BANGOR, MAINE.

PROCESS OF TANNING HIDES.

SPECIFICATION forming part of Letters Patent No. 250,241, dated November 29, 1881.

I Application filed February 4, 1878.

To all whom it may concern.-

Be it known that I, WILLIAM HARRIS, of Forest City, in the county of Washington and State of Maine, have invented certain new and useful Improvements in Processes for Expressing the WVater from and Equalizing the Thickness of Hides; and I do hereby declare that the following is a full, clear, and exact description of the invention, that will enable others skilled in the art to which it appertains to make and use the same, reference being bad to the accompanying drawing, forming a partof this specification, in which is shown a perspective of my machine.

My invention relates to an improvement in the art ofpreparinghides 5 and itconsistsin submitting them,after the tanning has been completed and the hides have been drenched or scrubbed, to the action of one or more pair of pressure-rollers having hard or unyielding surfaces,the effect of which is to remove the water or liquor remaining after the drenching or scrubbing, facilitating the subsequent drying and equalizing the thickness of the hide. The pressure of the hides between rollers subsequent to the drenching or scrubbing forms a new step in the process, and constitutes, in connection with the other and usual operations, a new and improved process of preparing the hides for the market. By the present method,

after tanning, the hides are taken from the tanning-vats and placed in a washer or scrubber, in which they are drenched with water. They are then removed and suspended until dried by draining and evaporationan operation requiring some two weeks or more. When dried the different parts vary greatly in thickness, and the hide must then be subjected to the operation of roughing or rubbing down the inequalities. The wet hide, even after scrubbing,

retains a considerable percentage of the tanning-liquor, which is wasted in the process of drying.

My improved method consists in passing the hides, after washing or scrubbing, through one or more pairs of heavy rollers, expressing the liquor and water, and at the same time reducing the hides to a uniform or nearly uniform thickness requiring little or no subsequent 5 roughing. These rollers may be either cold orheated; or, if more than one pairbe used, cold and hot rollers may be combined. A sufficient number of hotrollers may be used to completely dry the hide, or it may be partially dried and the method completed as at present.

My process of removing the water and liquor by the action of pressure-rollers, as will be observed, combines the .processes of drying and roughing, or at least contributes greatly to the subsequent performance of these opera 6o tions, enabling them, if necessary at all, to be done in very much less time. In addition to this, the combined water and liquor remaining in the hide, instead of being wasted by draining and evaporation, as now, maybe preserved, and by fortifying with fresh liquor to the required strength may be used in the vats, efi'ecting an important saving.

I will now proceed to explain an apparatus which is appropriate for my purpose by refer- 7o ence to the accompanying drawing, in which I have shown two sets of rollers, one being hollow to receive steam, and the other represented as cold.

Atais a suitable frame having rollers b We 0, having unyielding surfaces journaled therein, thejournal-boxes at being capable ofa slight vertical motion,making the rollers 12 c self-adjusting to hides of different thickness. This adjustment is regulated by a set-screw, e, acting upon a spring, f, placed on the journal-boxes 11. At 9 is a table, upon which the hide is presented to the rollers b b, represented as cold. Under the lower roller, 1), is a trough, h, for the reception of the expressed liquor, which is led from it by spouts to any convenient reservoir. From the rollers b b the hide passes to and between a second set of rollers, c 0, represented as heated by steam,z' 2' being the supply-pipes, which assist in equalizing the thickness of the 0 hide and in'expressing and evaporating the moisture. These rollers are revolved in any convenient manner, both running at equal speed, or one of the set speeded higher than the other, to cause friction on the surface of the grain side 5 of the hide, for the purpose of increasing its smoothness. I

I am aware that hides have hitherto been laced together to form abelt and fed between rollers suspended over the vats containing the Ice tanning-liquor, so as to be drawn through the liquor, exposing each part in order to its action.

I am also aware that hides have been subjected to pressure within the tannin g-vats, and subsequently passed between rollers to remove the liquor and make room for more, when the hides are again subjected to pressure within the vats, the two operations being repeated until. the hides are tanned; but this I do not claim, the submitting to pressure between rollers in my process being a step in regular order after the tanning has been entirely completed and the tanning-liquor removed as much as possible by drenching or washing, and serving as a substitute for the present operations of drying and roughing, as heretofore described, and not as a means of forcing the tanning-liquor into the hides.

What I claim as my invention, and desire to secure by Letters Patent, is-

1. The improvement in the art of manufacturing leather herein described, consisting in first submitting the hides to any ordinary tanning process, and after they have been tanned and drenched passing them between pressure-rollers having hard or unyielding surfaces, for the purpose of expressing the superfluous water and liquor and reducing the hides to a uniform thickness, substantially as set forth.

2. The improvement in the art of manufacturing leather herein described, consisting in first submitting the hides to any ordinary tanning process, and after they have been tanned and drenched passing them between heated pressure-rollers having hard or unyielding surfaces, for the purpose of expressing and evaporating the superfluous Water and liquor and reducing them to a uniform thickness, substantially as set forth.

In testimony that I claim the foregoing I have hereunto set my hand this 30th day of January, 1878.

WILLIAM HARRIS.

Witnesses:

THos. N. EGERY, WM. FRANKLIN SEAVEY. 

